Water security is a key issue for anyone in agriculture and one of the biggest hurdles to promoting development in northern Australia.

Now an idea first flagged by Sydney Harbour bridge engineer Dr John Bradfield in the 1930s, for a dam on the Fitzroy River, is getting a new push.

The proposed dam would hold 10,000 gigalitres near the Eden Bann weir, 50 kilometres north-west of Rockhampton, and cost at least $3 billion to build.

Rockhampton businessman Dominic Doblo says the enormity of the project has scared policy makers away in the past.

"This is what Rockhampton needs for its economy. Rockhampton is struggling enormously.

"Everyone is dreaming about a food bowl. We're not going to have any sort of food bowl or agricultural bowl or any sort of bowl without this scale of water.

"The storage capacity of this dam is 10,000 gigalitres, which by scale is the same size as Lake Argyle in the Ord River. The combined storage capacity of the Snowy Mountains is only 7,000 (gigalitres), so it's bigger than the Snowy Mountains."

Cattle industry identity Sir Graham McCamley is adding his support to the project.

He says it would take pressure off the Fairbairn Dam at Emerald.

"It's critical to the growth of those on the Capricorn Coast, Gladstone, Rockhampton to have a decent dam instead of building silly little dams that they've been doing.

"It's so important to keep the ones that are still already farming now they don't have enough water in the Fairbairn. Therefore if the Fairbairn just did Emerald area, and this backs right up as far as Tartrus and goes right up the Dawson probably near to Theodore it's

servicing a big area of people to grow all sorts of things, I think."

Sir Graham believes this the dam is an essential piece of infrastructure to encourage the wider development of northern Australia.

"I just think if they start this Northern Development here, (they'll move) from here to Emerald west and move gradually right through to where they want to end up way up near Karumba and right up near the Kowanyama and into that area.

"They'll move everything with them. They'll take all the silos, the roads, the main roads will all be justified."

Local mayor Margaret Strelow says it's something worth looking into, but it's not high on the priority list.

"They're not things that are high on our agenda to actually drive and to build, because we already have really strong robust water supplies to meet the needs of our community and for growing industry and agriculture nearby.

"[The] Regional Council already owns 20,000 megalitres of high priority water that's not currently being used and is available if there's a development or industry or proponent wanting to access that."

But Michael McCabe, from the Capricorn Conservation Counci,l isn't convinced the project is feasible

"We have a very wide flood plain and the potential would be for the river to cut around the side of the dam.

"Weirs have been possible on the Fitzroy, but not dams."

Mr McCabe says a dam would also pose a serious threat to the environment.

"Weirs and dams will raise the risk of toxic algae blooms which are already shown to infect our river.

"It would also create enormous risk of releasing the millions of tonnes of salt that lives in that ancient landscape."

Premier Campbell Newman says the Queensland Government will consider any proposals for a dam on the Fitzroy River, but it will be difficult to find the money to build it.

"I'm prepared to consider any infrastructure project, but what I want is a debate in Queensland right now about what projects are needed.

"Should we be building a dam there or should we be building a new hospital at Emerald or should there be a new school in another part of the state?